Abstract:
:Penicillinase (beta-lactamase I, EC 3.5.2.6) secreted by Bacillus cereus, strain 569/H, was covalently attached to aminoethyl cellulose via glutaraldehyde. The immobilized derivative shows increased thermostability and decreased susceptibility to conformational changes induced by certain substrates of penicillinase. The decline in the rate of hydrolysis of such substrates was consequently suppressed by immobilization. A marked increase in Km was observed with all substrates except for the unsubstituted 6-aminopenicillanic acid. The altered properties of the new derivative are attributed to the constraint imposed by immobilization on the conformational flexibility of the enzyme molecule. Thus, apart from obvious technological interest, immobilized penicillinase provides a useful model for the study of the role of flexibility in the function of an enzyme.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Klemes Y,Citri Ndoi
10.1002/bit.260210512subject
Has Abstractpub_date
1979-05-01 00:00:00pages
897-905issue
5eissn
0006-3592issn
1097-0290journal_volume
21pub_type
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